优选：精密管

山东大鼎金属材料有限公司Welded steel pipe is welded by butt weld or spiral weld. In the manufacturing method, it can be divided into low-pressure fluid conveying welded steel pipe, spiral welded steel pipe, direct rolling welded steel pipe, electric welded pipe and other precision steel pipe itself, metal deformation is more uniform, which makes precision steel pipe, part of which, in the process of hardening. For example, when the deformation part is hardened, the deformation will not spread to other non deformed parts. This ensures that the deformation of the pipeline during use will not cause damage or loss.山东大鼎钢管厂27siMn精密钢管的力学性能；抗拉强度屈服强度伸长率截面收缩率冲击吸收能冲击值力学性能试验方法；所有精密钢管都应满足要求。测试机械性能。测试力学性能的方法主要有两种，一种是拉伸试验，另一种是硬度试验。拉伸试验是将精密钢管制成试样，然后在拉伸试验机上拉断试样，然后测量一个或多个力学性能，通常只测量拉伸强度、屈服强度、断裂后伸长率和截面收缩率无缝钢管由优质碳素钢或合金钢制成，分为热轧和冷轧（拉拔）。